package my.assistant;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import android.app.ListActivity;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.content.pm.ResolveInfo;
import android.os.Bundle;
import android.view.View;
import android.widget.ListView;
import android.widget.SimpleAdapter;

public class Assistant extends ListActivity
{
	private static String BLANK = "";

	/** Called when the activity is first created. */
	@Override
	public void onCreate(Bundle savedInstanceState)
	{
		super.onCreate(savedInstanceState);
		Intent intent = getIntent();
		String path = intent.getStringExtra("my.assistant.Path");

		if (path == null)
		{
			path = BLANK;
		}

		setListAdapter(new SimpleAdapter(this, getData(path), android.R.layout.simple_list_item_1, new String[]
		{ "title" }, new int[]
		{ android.R.id.text1 }));
		getListView().setTextFilterEnabled(true);
	}

	private List<? extends Map<String, ?>> getData(String prefix)
	{
		List<Map<String, ?>> myData = new ArrayList<Map<String, ?>>();

		Intent mainIntent = new Intent(Intent.ACTION_MAIN, null);
		mainIntent.addCategory(Intent.CATEGORY_EMBED);
		mainIntent.setPackage("my.assistant");

		PackageManager pm = getPackageManager();
		List<ResolveInfo> list = pm.queryIntentActivities(mainIntent, 0);

		if (null == list)
			return myData;

		String[] prefixPath;

		if (BLANK.equals(prefix))
		{
			prefixPath = null;
		} else
		{
			prefixPath = prefix.split("/");
		}

		int len = list.size();
		Map<String, Boolean> entries = new HashMap<String, Boolean>();
		for (int i = 0; i < len; i++)
		{
			ResolveInfo info = list.get(i);
			CharSequence labelSeq = info.loadLabel(pm);
			String label = labelSeq != null ? labelSeq.toString() : info.activityInfo.name;

			if (prefix.length() == 0 || label.startsWith(prefix))
			{
				String[] labelPath = label.split("/");
				String nextLabel = prefixPath == null ? labelPath[0] : labelPath[prefixPath.length];
				if ((prefixPath != null ? prefixPath.length : 0) == labelPath.length - 1)
				{
					addItem(myData, nextLabel, activityIntent(info.activityInfo.applicationInfo.packageName,
					        info.activityInfo.name));
				} else
				{
					if (entries.get(nextLabel) == null)
					{
						addItem(myData, nextLabel, browseIntent(BLANK.equals(prefix) ? nextLabel : prefix + "/"
						        + nextLabel));
						entries.put(nextLabel, true);
					}
				}
			}
		}
		return myData;
	}

	private Intent activityIntent(String pkg, String componentName)
	{
		Intent result = new Intent();
		result.setClassName(pkg, componentName);
		return result;
	}

	private Intent browseIntent(String path)
	{
		Intent result = new Intent();
		result.setClass(this, Assistant.class);
		result.putExtra("my.assistant.Path", path);
		return result;
	}

	private void addItem(List<Map<String, ?>> data, String name, Intent intent)
	{
		Map<String, Object> temp = new HashMap<String, Object>();
		temp.put("title", name);
		temp.put("intent", intent);
		data.add(temp);
	}

	@SuppressWarnings("unchecked")
	@Override
	protected void onListItemClick(ListView l, View v, int position, long id)
	{
		Map<String, ?> map = (Map<String, ?>) l.getItemAtPosition(position);
		Intent intent = (Intent) map.get("intent");
		startActivity(intent);
	}
}